A precise measurement of the magnetic field in the corona of the black hole binary V404 Cygni.

Observations of binary stars containing an accreting black hole or neutron star often show x-ray emission extending to high energies (>10 kilo--electron volts), which is ascribed to an accretion disk corona of energetic particles akin to those seen in the solar corona. Despite their ubiquity, the physical conditions in accretion disk coronae remain poorly constrained. Using simultaneous infrared, optical, x-ray, and radio observations of the Galactic black hole system V404 Cygni, showing a rapid synchrotron cooling event in its 2015 outburst, we present a precise 461 ± 12 gauss magnetic field measurement in the corona. This measurement is substantially lower than previous estimates for such systems, providing constraints on physical models of accretion physics in black hole and neutron star binary systems.

Descentralización y desarrollo local: construimos el futuro con nuestras propias manos / Decentralization and local development

Describe el proceso de descentralización y fortalecimiento municipal, poniendo énfasis en la participación de la población en las decisiones y programas de acción de la municipalidad, como condición fundamental para que esta institución se convierta en el eje de desarrollo de la comunidad...

[Measurement of maximal oxygen uptake in a Chilean population sample]. / Medición del consumo máximo de oxígeno en una muestra de la población chilena.

BACKGROUND: Maximal oxygen uptake is considered by the International Biological Programme as the international standard of cardiorespiratory adequacy and physical condition. AIM: To measure maximal oxygen uptake in normal Chilean subjects, to establish normal reference values. SUBJECTS AND METHODS: Maximal oxygen uptake was measured in 2,203 subjects (451 women) aged 7 to 66 years old, during maximal exercise in a cyclo-ergometer or treadmill. This sample included trained sportsmen. RESULTS: Maximal oxygen uptake in men was 3.4 +/- 0.8 Vmin (range 1.1 to 5.6) or 55.2 +/- 9.2 ml/kg/min (range 23.8 to 83.2). In women, the figures were 2.55 +/- 0.55 l/min (range 0.87 to 3.82) or 47.5 +/- 8.0 ml/kg/min (range 20.8 to 76.3). These values decrease 0.65 ml/kg/min per year of age. CONCLUSIONS: These values can be useful as a normal reference for epidemiological, clinical or sportive purposes.

Comparación de dos espirómetros de sello rodante y dos de tipo Fleisch (neumotacómetro) / Comparison between 2 rolling seal and 2 Fliesch type spirometers (pneumotacometer)

El rendimiento de la espirometría depende de la precisión y confiabilidad del espirómetro, de la técnica del examen y de los valores de referencia. Existiendo diversos tipos de espirómetros, comparamos las lecturas entre dos aparatos de sello rodante (Sensor Medics modelo 922) y 2 tipo Fleisch (Vitalograph, modelo Compact), obtenidas de 16 voluntarios, 8 hombres y 8 mujeres. Se practicó en cada equipo una espirometría al día, en 4 días sucesivos. Los exámenes se hicieron de acuerdo a recomendaciones de la American Thoracic Society (ATS). No hubo diferencias significativas en las variables consideradas entre instrumentos del mismo tipo. En la comparación entre los espirómetros de sello rodante y los de tipo Fleisch, se encontraron para estos últimos, lecturas de volumen y flujo sistemáticamente inferiores (p<0,05)

Maximal oxygen uptake in Chilean workers of normal nutritional status.

Maximum oxygen uptake (VO2max) was measured directly and predicted from cardiac frequency measurements in 54 healthy Chilean industrial workers aged 20 to 55 years, together with assessment of their dietary intake, body composition and blood chemistry. Measurement of VO2 was performed on a motor-driven treadmill. The predicted VO2max was obtained using a cycle ergometer by two methods: 1) the Astrand-Ryhming nomogram and 2) the linear relationship between "steady state" heart rate (HR) and submaximum work, with subsequent extrapolation to "maximum" heart rate. Extrapolation of the HR/load regression line to 170 bpm permitted determination of the physical working capacity at 170 bpm (W170). VO2max for the 20-29 year group (Group I) averaged 3624 ml.min-1 and decreased to 3066 ml.min-1 in the 50-55 year group (Group IV). Lower values were obtained using the Astrand-Ryhming nomogram and HR/load regression (-15% and -9% respectively). W170 was also affected by age (Group I: 190.6 W and Group IV: 158.5 W). No significant correlation were found between VO2max and plasma variables, with the exception of cholesterol (r = 0.59). On the contrary, anthropometric variables showed significant correlations with VO2max, which permitted the prediction of VO2max using multiple regression equations. The two best correlations were: 1. VO2max = 0.800 - 0.0225.(A) +0.0189.(W)+1.26.(H) (r = 0.87; p less than 0.001) 2. VO2max = 0.996 - 0.0176.(A) + 0.025.(W) + 0.838.(H) + 0.0255.(LBM) (r = 0.88; p less than 0.001) where A = years of age; W = body weight in kg; H = height in m and LBM = lean body mass in kg.